IIS - Remove trailing slash when directory - html

Question

I want to remove trailing slashes from all requests from "/" to "", even when it's a directory. For instance:
Folder: http://bleh.local/sign-in/
File to be served: http://bleh.local/sign-in/index.html
Default document: index.html
I would like to redirect it to "http://bleh.local/sign-in"
Expected behavior: /sign-in/ redirected to /sign-in
Actual behavior: /sign-in redirected to /sign-in/
Web.config:
<rule name="RemoveTrailingSlashRule1" enabled="true" stopProcessing="true">
<match url="(.*)/$" />
<conditions>
<add input="{REQUEST_FILENAME}" matchType="IsFile" negate="true" />
</conditions>
<action type="Redirect" url="{R:1}" />
</rule>
applicationHost.config:
<sectionGroup name="rewrite">
<section name="globalRules" overrideModeDefault="Allow" allowDefinition="AppHostOnly" />
<section name="rules" overrideModeDefault="Allow" />
<section name="outboundRules" overrideModeDefault="Allow" />
<section name="providers" overrideModeDefault="Allow" />
<section name="rewriteMaps" overrideModeDefault="Allow" />
<section name="allowedServerVariables" overrideModeDefault="Allow" />
</sectionGroup>
With this setup, I get infinite redirects because I removed this instruction from the original setup:
<conditions>
<add input="{REQUEST_FILENAME}" matchType="IsDirectory" negate="true" />
</conditions>
I think my problems come from this: https://support.microsoft.com/en-ca/help/298408/iis-generates-courtesy-redirect-when-folder-without-trailing-slash-is
Any ideas?
Note: How can I configure IIS to serve directories without trailing slashes and always serve relative to root path? is not solving my problem. The backslashes are added consistently.

Answer 1

This is because of the <defaultDocument> in IIS.
<defaultDocument> rule is enabled in IIS by default which forces the page to be redirected to the url with trailing slash, if it did not find a file. domain/sign-in/
<rule name="RemoveTrailingSlashRule1" enabled="true" stopProcessing="true">
<match url="(.*)/$" />
<conditions>
<add input="{REQUEST_FILENAME}" matchType="IsFile" negate="true" />
</conditions>
<action type="Redirect" url="{R:1}" />
</rule>
Now this rule, matches the url with the trailing slash (and matches directory) and in turn redirects to the one without the trailing slash. domain/sign-in which creates a loop.
The solution is to add the rule<defaultDocument enabled="false"></defaultDocument>.
https://learn.microsoft.com/en-us/iis/configuration/system.webserver/defaultdocument/